1. Field of the Invention
The invention relates to a snap-action spring drive for load-reversing switches of multiple contact switches, which includes a storing spring that can be loaded by a drive having a shaft which rotates either clockwise or counterclockwise, and an element for controlling the contact movement, which preferably is a cam disk or a connecting link control and is driven during the reversing process by the storing spring, performs a rotational movement.
2. Discussion of the Background Information
Conventional load-reversing switches for multiple contact switches of voltage regulating transformers have a resistance quick throw-over switch having switch contact shafts which are controlled by means of a cam disk drive driven by an energy storage device. In this connection, the cam disk is moved from one end position to another, and back again by a back and forth movement, regardless of the particular direction of movement of the selector. This means that the contacts which last closed during the movement of the cam drive in one direction open first during the reverse movement, or that the contacts which first opened during the movement in one direction close last during the reverse movement.
This rigid contact sequence during the load-reversing operation is unsuitable for thyristor load-reversing switches.